The mouse that Douglas Engelbart and SRI's chief engineer, Bill English, demonstrated to 1,000 people in San Francisco 40 years ago. Click on the image above for more photos.
Stanford Research Institute

If you use a computer, it's almost certain you owe some thanks for the "personal" nature of the device to Douglas Engelbart. Tuesday is the 40th anniversary of a day that should mean a lot if you enjoy the interactivity of your machine.

On December 9, 1968, Engelbart, director of Stanford Research Institute's Augmentation Research Center, wowed the computing world with a presentation in which he unveiled, for the first time, the work he and his SRI team had been doing.

Among the innovations Engelbart showed that day in San Francisco were the world's first mouse, the first hyperlinks, and the first navigable windows. And though it's a long way from that presentation to your laptop, the bloodline is clear. Click here to see more photos from a day that changed computing forever.